1. Field of the Invention
The present invention relates to a soft and bulky non-woven fabric having light weight, high strength and excellent hand without waxy feeling.
2. Description of the Prior Art
In the recent increasing consumption of non-woven fabrics, the demand for lower weight non-woven fabrics of 10.about.50 g/m.sup.2, above all from 15 to 35 g/m.sup.2, is remarkably arising as for surface liner of disposal sanitary materials. It is required to non-woven fabrics used in this field to have following preferable properties, that are light weight, high strength, bulky, less fluffs, soft hand and to give agreeable feeling to human skin contacting with. The non-woven fabrics made by a binder adhesion process commonly utilized hitherto have such drawbacks that their hand become harder by increasing the quantity of the binder used in request to improve the strength, that the kinds of binders applicable to produce non-woven fabrics for surface liners of disposal diaper or sanitary napkin is strictly limited by the regulation of residual formalin in the non-woven fabrics, and that as the hydrophobic synthetic fibers such as polyolefin fiber and polyester fiber are coming to the main raw materials of non-woven fabrics, the difficulty to keep both of soft hand and high strength of non-woven fabrics made by a binder adhesion process is increasing from the view points of technology and economy.
In the above mentioned background, recently a process for producing non-woven fabrics so called no-binder process, by which structure of the non woven fabrics is stabilized by fixing the comprising fibers by melt adhesion of heat adhesive fiber, is coming before footlight obtaining somewhat good results of low equipment cost and low energy consumption. However, the waxy feeling possessed by hydrophobic fibers in themselves is perceived more apparent when the fibers become more fine ones. So, the unpleasant feeling caused by the waxy feeling is growing to a new problem on such products as sanitary materials which are used contacting with human skin in direct and are main uses of light weight non-woven fabrics.
The present inventors have made streneous studies to obtain a bulky and soft hand non-woven fabric which retains a high strength on light weight and also is provided non-waxy feeling, and have attained this invention by finding that the utilization of both foamed fibers and heat adhesive fibers as raw materials of non-woven fabric solves above-mentioned problems.